1. Manage The Display
The display is the one component on any tablet that uses the most power. The new iPad uses more LEDs to illuminate the display, which has twice the resolution and four times the pixels of its predecessor. Apple tests its displays at 50% brightness to get its numbers.
Rather than use the auto-brightness setting, which adjusts the display's brightness to match the amount of ambient light, use the manual controls. I have my iPad's display set to about 25%-30% brightness. That's still plenty bright for indoor use (even during the day, when it's sunny out). If you're going to be in a dark room, such as an auditorium, adjust it down further to lengthen the battery life even more.
One of iOS 5.1's best features is the notification center. It delivers notifications to the home screen in a less-obtrusive way than before--but it can also wreck your battery.
Many notifications will turn on the iPad's display when they arrive. Even if the display is on for 5 or 10 seconds, it is using more battery power than when off. In the Notifications setting menu, turn Notifications to "off" for as many apps as possible. Second, for those apps which you absolutely must have notifications, turn the "View on Lock Screen" setting off. This ensures that when notifications arrive, they won't turn on the iPad's display. Third, set the "Repeat Notification" tool to off.
Aside from the display, the wireless radios in any tablet rank second in terms of draining the battery. Though it requires a little bit of work, there are some easy steps available to help maximize battery life.
First, know what networks are available and how your device will use them. All iPads have Wi-Fi and Bluetooth. The AT&T/Verizon iPads also have 3G/4G buried inside. The iPad will always default to Wi-Fi when Wi-Fi is available, and won't resort to using 3G/4G unless Wi-Fi isn't available. If your employer offers Wi-Fi in the office--or if you have Wi-Fi in your hotel room, or in your home office, etc.--turn the cellular radio off completely. Also make sure that the Bluetooth radio is off unless you're actively using a Bluetooth accessory, such as a keyboard.
Conversely, if you're going to be outside and you know Wi-Fi won't be available at all, turn off the Wi-Fi radio and leave on the cellular radio instead.
In addition to the cellular radios, managing location services (GPS) is a key factor to maintaining good battery life. First, you can choose to turn off location services entirely. This is your best bet to having a positive impact on battery life. If you need to have location services on, limit them to a few key apps and make sure you're managing which apps have access to your location data.
5. Email / iCloud
When the iPad wakes itself up to check for email or other synced data (such as calendar/contacts), it is slurping power. The more often the iPad checks for this data, the more power it consumes. To help increase battery life, turn off push email entirely. Rather than have the device sync once every 15, 30, or 60 minutes, choose to have it sync manually instead. This means the iPad will only check for mail when you open the email app rather than constantly.
With these handy tips under your belt, it should be quite easy to get much more than the 9-10 hours of advertised battery life from the new iPad.
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